Sphingosylphosphorylcholine induces degranulation of mast cells in the skin and plasma exudation in the ears of mice

Role of Sphingosylphosphorylcholine in Tumor and Tumor Microenvironment

Sphingosylphosphorylcholine (SPC) is a unique type of lysosphingolipid found in some diseases, and has been studied in cardiovascular, neurological, and inflammatory phenomena. In particular, SPC’s studies on cancer have been conducted mainly in terms of effects on cancer cells, and relatively little consideration has been given to aspects of tumor microenvironment. This review summarizes the effects of SPC on cancer and tumor microenvironment, and presents the results and prospects of modulators that regulate the various actions of SPC.

Novel effects of sphingosylphosphorylcholine on invasion of breast cancer: Involvement of matrix metalloproteinase-3 secretion leading to WNT activation

Sphingosylphosphorylcholine (SPC) participates in several cellular processes including metastasis. SPC induces keratin reorganization and regulates the viscoelasticity of metastatic cancer cells including PANC-1 cancer cells leading to enhanced migration and invasion. The role of SPC and the relevant mechanism in invasion of breast cell are as yet unknown. SPC dose-dependently induces invasion of breast cancer cells or breast immortalized cells. Reverse transcription polymerase chain reaction and Western blot analyses of MCF10A and ZR-75-1 cells indicated that SPC induces expression and secretion of matrix metalloproteinase-3 (MMP3). From online KMPLOT, relapse free survival is high in patients having low MMP3 expressed basal breast cancer (n=581, p=0.032). UK370106 (MMP3 inhibitor) or gene silencing of MMP3 markedly inhibited the SPC-induced invasion of MCF10A cells. An extracellular signal-regulated kinase (ERK) inhibitor, PD98059, significantly suppressed the secretion and the gelatinolytic activity of MMP3, and invasion in MCF10A cells. Over-expression of ERK1 and ERK2 promoted both the expression and secretion of MMP3. In contrast, gene silencing of ERK1 and ERK2 attenuated the secretion of MMP3 in MCF10A cells. The effects of SPC-induced MMP3 secretion on β-catenin and TCF/lymphoid enhancer factor (LEF) promoter activity were examined since MMP3 indirectly activates canonical Wnt signaling. SPC induced translocation of β-catenin to nucleus and increased TCF/LEF promoter activity. These events were suppressed by UK370106 or PD98059. Wnt inhibitor, FH535 inhibited SPC-induced MMP3 secretion and invasion. Taken together, these results suggest that SPC induces MMP3 expression and secretion via ERK leading to Wnt activation.

Novel inhibitory effects of cardamonin on thromboxane A2-induced scratching response: Blocking of Gh/transglutaminase-2 binding to thromboxane A2 receptor

Alpinia katsumadai is known to suppress thromboxane A2 (TXA2) receptor agonist-induced scratching in mice. The specific components of A. katsumadai responsible for these biological effects, however, are not known. In the present study, we investigated whether cardamonin (CDN), one of major principles of A. katsumadai, has suppressive effects on TXA2-induced scratching in mice. Scratching induced by U46619 (the TXA2 receptor agonist) at a dose of 10nmol/site was shown to be suppressed by CDN (0.1nmol-0.5nmol/site). Suppression of the U46619-induced scratching response by CDN was found to be unrelated to competition with the ligand at the TXA2 receptor, since CDN did not suppress [(3)H] SQ29548 (the TXA2 receptor antagonist) binding to TXA2 receptor. TXA2 receptor expression in A549, HaCaT, and SH-SY5Y cell lines was examined and determined to be significant in the A549 and SH-SY5Y cell lines. Further, binding of high molecular G protein Gh/transglutaminase-2 (Gh/Tgase-2) to TXA2 receptor was confirmed in the A549 and SH-SY5Y cells by co-immunoprecipitation. CDN suppressed the binding of TXA2 receptor with Gh/Tgase-2, which also acts as a G protein involved in TXA2 signaling. These results suggested that CDN suppresses TXA2 receptor agonist-induced scratching by suppressing TXA2 signaling, specifically via blocking of the binding of Gh/Tgase-2 to TXA2 receptor.

Isolation of Soil Microorganisms Having Antibacterial Activity and Antimigratory Effects on Sphingosylphosphorylcholine-induced Migration of PANC-1 Cells

To obtain soil microorganisms producing antimigratory activity which is important in controlling the metastasis of cancer cells, more than three hundreds of soil microbes were isolated from sixteen soil sources including Namsan mountain and designated as DGU1001-10338. At first, their antibiotic activities were examined by paper-disc method. More than 40 soil microbes produced compounds with antibiotic activity. Then, antimigratory activities of selected soil microorganisms were examined in a sphingosylphosphorylcholine-induced migration assay in PANC-1 cells. Six of 42 soil microorganisms having antibacterial activity also had more than 45% inhibitory activity on migration of PANC-1 cells. These results suggested that selected soil microorganisms were a useful starting point to find compounds for controlling metastasis of cancer cells.